Date of Graduation


Document Type


Degree Name

Master of Science in Cell & Molecular Biology (MS)

Degree Level



Biological Sciences


Sha Jin

Committee Member

Gisela Erf

Second Committee Member

Robert Beitle


Biological sciences, CD154, Yeast surface display


The CD154 (CD40L) is a member of tumor necrosis factor (TNF) family that plays a crucial role in regulation of both cell-mediated and humoral immunity by activating antigen presenting cells (APCs). Previously, studies in the laboratory demonstrated that yeast surface display system allows the expression of biologically functional antigen, such as subunit HA, against influenza virus. Yeast surface display system seems to be an excellent system to be utilized to develop anti-influenza virus vaccine. Thus, it is of interest to study the adjuvant function of CD154 on the subunit HA vaccine against influenza virus. In this project, the CD154 encoding gene was isolated from mouse spleen tissue and sub-cloned into a yeast cell surface protein display vector. Display of CD154 on yeast surface was investigated and confirmed through immunofluorescence microscopy, Western blot, and flow cytometric analysis. To elevate high level display of CD154 on yeast surface, the time course of CD154 surface display was determined and used for optimizing the yeast expression system. This work laid out the foundation for using CD154 as an adjuvant for recombinant yeast influenza vaccines. The adjuvant effect of yeast surface displayed CD154 is now tested in animal studies in this laboratory.